Egg donation and mitochondrial disease

There has been a fair amount in the press recently about mitochondrial disease and some possible new ways of treating it. The latest technique is fairly controversial and the HFEA is currently running a consultation about whether or not it should be approved in this country.

This is a fairly specialist area so it may not be something you know about, so before getting into it you might like first to look at our pages on the human egg cell and also our Glossary on definitions of relevant terminology.

In brief, mitochondria are microscopic structures inside our cells that mainly provide energy for the cells, but also have other important functions to keep the cells healthy and working properly. They also contain some DNA, which is the genetic material that holds our genes. The main bulk of our DNA is stored in the nucleus of the cell and we get half of this from our father and half from our mother. However, the DNA in the mitochondria is different in that it only comes from our mother. Sometimes this DNA gets damaged or has flaws in it, causing mitochondrial disease, and which can therefore be passed from mother to child.

In order to reduce the likelihood of passing any mitochondrial disease from one generation to the next, scientists have come up with a sophisticated technique for bypassing it. This latest technique involves taking the DNA from the nucleus of the mother’s egg and transplanting it into the egg from a healthy donor in place of the donor’s nuclear DNA. In this way the resulting egg would then have the mother’s nuclear DNA (the main store of genes) but the donor’s healthy mitochondrial DNA, which would hopefully prevent the mitochondrial disease from being passed on.

This technique throws up a number of important questions that need to be clarified before the technique is approved. If you would like to have a say in this important debate you can visit the HFEA website and get involved.